This invention relates to a picture blur-alarm device for a camera. When a foreground object or camera body is shifted during the shutter operation, intolerable blur will appear in a picture. The blur denotes an indistinct portion of a picture which results from the relative movement between a film and an image of an object formed on the film through a lens system. With a conventional camera of aperture priority type, for example, when it is detected that an insufficient amount of light comes from a foreground object, the shutter speed is set slow, and then the high probability of blurring taking place is indicated. However, this type of camera cannot clearly determine in advance whether blurring appearing in a picture falls within an allowable limit. Therefore, it is only after the development of an exposed film that judgment can be made as to whether blurring has occurred to an extent falling within an allowable range. Accordingly, the possibility is great that an important picture will be lost.